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diff --git a/sw/os8/v3d/sources/fortran/all/atan2.ra b/sw/os8/v3d/sources/fortran/all/atan2.ra
new file mode 100644
index 0000000..0c1df14
--- /dev/null
+++ b/sw/os8/v3d/sources/fortran/all/atan2.ra
@@ -0,0 +1,80 @@
+/
+/
+/
+/	A  T  A  N  2
+/	-  -  -  -  -
+/
+/SUBROUTINE	ATAN2(Y,X)
+/
+/ VERSION 5A 4-27-77  PT
+/
+	SECT	ATAN2
+	JA	#ATAN2
+	TEXT	+ATAN2 +
+ATN2XR,	SETX	XRATN2
+	SETB	BPATN2
+BPATN2,	FNOP
+	0
+	0
+XRATN2,	F 0.0
+YCOR,	F 0.0
+XCOR,	F 0.0
+FPIAT2,	2		/PI
+	3110
+	3755
+ATPI,	F 1.570796		/PI/2
+	ORG	10*3+BPATN2
+	FNOP
+	JA	ATN2XR
+	0
+AT2RTN,	JA	.
+	BASE	0
+#ATAN2,	STARTD
+	FLDA	10*3
+	FSTA	AT2RTN
+	FLDA	0
+	SETX	XRATN2
+	SETB	BPATN2
+	BASE	BPATN2
+	LDX	1,1
+	FSTA	BPATN2
+	FLDA%	BPATN2,1	/ADDR OF Y
+	FSTA	YCOR
+	FLDA%	BPATN2,1+	/ADDR OF X
+	FSTA	XCOR
+	STARTF
+	FLDA%	YCOR		/GET Y - THE TAN
+	FSTA	YCOR		/SAV FOR A SECOND
+	LDX	1,2		/POSITIVE X
+	JEQ	ATN0
+	JGT	ATN1
+	LDX	0,2
+ATN1,	FLDA%	XCOR		/GET X - THE QUADRAND
+	FSTA	XCOR		/+MOVE IT TO A SAFE PLACE
+	JEQ	ATASP
+	FLDA	YCOR		/Y/X
+	FDIV	XCOR
+	FSTA	YCOR
+	EXTERN	ATAN
+	JSR	ATAN		/CALL ATAN
+	JA	.+4		/TAKE ARCTAN OF Y/X
+	JA	YCOR
+	FSTA	YCOR		/SAVE IT AWAY
+	JGE	A2		/SKIP IF 1 OR 3 Q
+	FADD	FPIAT2		/ADD PI FOR 4TH Q
+	FSTA	YCOR
+A2,	JXN	AT2RTN,2
+	FLDA	YCOR
+	FSUB	FPIAT2		/SUB PI FOR 2ND+3RD QUADS
+	JA	AT2RTN
+ATASP,	FLDA	ATPI		/X=0 MEANS +-PI/2
+	JXN	ATNG,2
+	FNEG
+ATNG,	JA	AT2RTN
+ATN0,	FLDA%	XCOR
+	JLT	POSX		/IF X POS,ANS IS 0
+	FCLA
+	JA	AT2RTN
+POSX,	FLDA	FPIAT2		/OTHERWISE,ANS IS PI
+	JA	AT2RTN
+